A known technique used in a digital multiple-service network, such as e.g. the ISDN network (ISDN, Integrated Services Digital Network), is transmission of information between two predetermined subscriptions using computers provided with PC cards applicable for ISDN D-channel data transfer. However, such a procedure requires the setup of a separate connection between the subscriptions in question.
Another prior-art method is e.g. the one described in specification FI 971716, whereby information is transmitted to a telecommunication terminal by a technique in which the terminal functions as a passive party only receiving information independently, without requiring any actions on the ISDN user's part. In this case, the information provider activates the transmission without the receiver's acknowledgement. This arrangement can be used to direct advertising, marketing or similar information to certain target groups e.g. according to the location of subscriptions, which can be determined on the basis of subscriber numbers or on some other corresponding basis.
Moreover, a previously known solution in the ISDN system is to implement services in a telephone exchange or as a separate intelligent network application. In the GSM network (GSM, Global System for Mobile Communications), interactive services are implemented using short messages.